Verifying SD Cards

Hi Theo,

Thats the same I did with my fairphone. Officially they only support 32 GM SD-cards. I use a 64 GB wit a first partition with 20 GB and tge second with the rest using ext4. Using Apps2SD or link2SD you can use the ext4 partition pretty like internal flash.

Marte

OK, but it's a tradeoff made by Microsoft. You don't get to pick the standard. You can choose to circumvent it and deal with any consequences.

It's like the highway speed limit. Somebody else set that arbitrary limit well below the capabilities of most automobiles. Those who stay below it experience fewer undesirable consequences than those who don't.

I suppose if you had millions

My win7 C: drive has 987,441 files.

Up to that point it's a

There's nothing to prevent YOU doing anything you want. There are compatibility and marketing forces driving MS offerings.

You've lost me. There is no rule that you can't use a FAT32 volume over

32 GB under windows. You just can't easily make it. I formatted my 64 GB SDXC card in one partition with FAT32. I'm not sure what you are trying to say. Where is the down side?

Ok, how many are "small"? Assuming each one wastes 16 kB, that's still just 32 MB total. Much less than 0.1% of a 32 GB SD card.

I have no idea what you are talking about here.

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Rick C

The other aspect of this tradeoff is that many operations need to work on whole clusters or sectors, so you suffer the bandwidth issue of needing to send and receive much more unnecessary data for what would otherwise be a small operation.

On Wed, 4 May 2016 18:44:24 -0400, rickman Gave us:

Windows being able to recognize and actually read files written past that point on the drive. Doh!

AFAIK, Windows has no problem reading FAT32 volumes up to 2TB. It's just that recent versions of FDISK (or equivalent) won't let you create one bigger than 32GB. The FDISK from Win98 had no such restriction. Third party versions can do that as well.

On 04 May 2016 18:41:09 +0100 (BST), Theo Markettos declaimed the following:

Try finding 1GB Compact Flash cards! (My BOSS BR-600 won't work with

2GB CF cards -- though for real laughs, I have a 128MB [yes MB] TransFlash sitting in arm's reach)

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	Wulfraed                 Dennis Lee Bieber         AF6VN 
    wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/

I agree. We obviously had different math teachers.

Hint: 10e6 is ten million. 10e3 is ten thousand.

Clifford Heath.

On Wed, 4 May 2016 18:44:24 -0400, rickman declaimed the following:

Since 16kB is the cluster size for Windows on 32GB partitions... NTFS is only 4kB per cluster up to multiple TB partitions.

But one may want to consider what the inherent SD card allocation unit is (and if you can get the format to align the clusters with allocation units).

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	Wulfraed                 Dennis Lee Bieber         AF6VN 
    wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/

If you can make what you want and the result makes you happy, there's no downside for you. If you expect broad support by the industry so that everything just works, that's another issue. MS cares about the latter.

I think we had different math teachers...

10e6 x 16 x 10e3 = 16 x 10e9 bytes

I concur.

>

On Wed, 04 May 2016 18:17:33 -0500, Robert Wessel Gave us:

The biggest problem with FAT32 is the 4GB file size limitation.

Handcuffs movie lovers and handcuffs iso image size as well.

On Thu, 5 May 2016 11:28:15 +1000, Clifford Heath Gave us:

Bwuahahahaha!

Mike is at least an order of magnitude dumber than everyone in Usenet as well.

You are correct, I messed up the notation. how about I say One million files times 16 thousand bytes wasted per file = 16GB

I wouldn't know...

But I do know that my IQ is a couple of dB lower on a bad day.

Oops. Not allowed to use dB that way :)

What "broad" support? FAT32 works regardless of the partition size. Do you know of any devices that won't work with a large FAT32 partition? Microsoft products work with it.

Yeah, that's the "new" math. Where have *you* been?

Glad we are finally on the same page.

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Rick C

Yeah, I used to use a Magellan handheld GPS with the same issues. Heck, earlier units didn't even work with 512 cards, or at least would only use the first 256 MB. I have a small collection of 1GB SD cards just in case I want to go back to using that unit.

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Rick C

Why not? dB is relative power, in your case, "brain" power.

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Rick C

That was most likely the decision for that particular limit. The reason why there are incremental jumps between the formats is that SD Cards use serial addressing, and each card type uses a fixed number of bits for addressing giving a maximum storage size. The newer card types increase the number of bits to give more capacity, this would slow down access unless the bit clock was also increased, and that requires new reader hardware.

---druck

NTFS isn't good for SD cards, its a journalled filing system meaning a lot more writes, and would work very inefficiently if data was continually flushed to the card, if it isn't flushed it would corrupt frequently if not properly unmounted before removal.

As with any flash, the it is only possible to write in large blocks, this can be anything from 4K to 256MB, which is why there is such there is such a large difference in random write performance between different cards.

---druck